A sensible thermal energy storage (TES) system is studied using Hytherm 600 oil as the storage medium and a 30:70 ethylene glycol–water (EG-W) mixture as the discharging fluid, owing to its extended operating temperature range (− 14 ◦C to 105 ◦C) at atmospheric pressure. The EG-W mixture alleviates the working limitations of pure water by lowering the freezing point and elevating the boiling point, making it suitable for solar thermal systems in colder climates and for low-temperature industrial heat recovery without pressurized systems. The analyses establish that higher charging temperatures strongly promote stratification, effectively countering the mixing induced by higher discharge rates. The insights derived from the study establish a crucial foundation for configuring effective TES systems with non-conventional discharging fluids for various low-temperature applications.
